Sporting object producing endless debate (6)
I believe the answer is:
discus
'sporting object' is the definition.
(I know that discus is a type of sports equipment)
'endless debate' is the wordplay.
'endless' means to remove the last letter.
'debate' becomes 'discuss' (to discuss something is to debate it).
'discuss' with its last letter removed is 'DISCUS'.
'producing' acts as a link.
(Other definitions for discus that I've seen before include "missile launched" , "Sports projectile" , "Olympic throwing event" , "Athletics field event" , "Field sport" .)